<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script>
			function add(x,y,fun){
				return x+y+fun(x,y);
			}
			var num = add(4,5,function(x,y){
				return x*y;
			});
			alert(num);;
			function test(a,b){
				return a+b;
			}
			var num1 = add(5,6,test);
			alert(num1);
		</script>
	</head>
	<body>
	</body>
</html>
